PROBLEM TO BE SOLVED: To provide an immunostimulant which is derived from an ocean biomass resource, and can stimulate living-organism immunity protection capability, and to provide food containing the same and a pharmaceutical composition.SOLUTION: The immunostimulant is characterized by containing extracts from one or plurality of fishes belonging to one of seriola carangidae perciformes, sujidara department gadiformes genus sokotara, and tojin department gadiformes genus sokotara, or from a part of the extracts, and by having activity for increasing an immunity reaction in an animal inflected with herpes simplex virus (HSV). There are also provided the food containing the immunostimulant and the pharmaceutical composition.COPYRIGHT: (C)2012,JPO&INPIT【課題】海洋性バイオマス資源に由来し、生体免疫防護能を賦活できる免疫賦活剤、ならびにこれを含む食品および医薬組成物を提供する。【解決手段】スズキ目アジ科ブリ属、タラ目ソコタラ科スジダラ属、およびタラ目ソコタラ科トウジン属のいずれかに属する1または複数の魚類の魚体またはその一部からの抽出物を含み、単純ヘルペスウィルス(HSV)に感染した動物における免疫反応を増強させる活性を有することを特徴とする免疫賦活剤、ならびにこれを含む食品および医薬組成物。【選択図】図1